Statistical analysis of solar radiation models onto inclined planes for climatic conditions of Batman (Turkey)

Solar energy is one of the most widely used renewable energy resources in the world. A drawback, common to the photovoltaic systems (PV) is their unpredictable nature and their output cannot be accurately predicted, because, these systems are dependent on climatic conditions. Solar radiation data are the best source of information for proper design of PV systems. In this study; hourly tilted surface solar radiation is measured at different slope angles in Batman (Turkey). Selected models were compared on the basis of the statistical error tests; mean square errors (MSE), mean absolute errors (MAE) and root mean square errors (RMSE) and mean absolute percentage error (MAPE). Besides, a new equation was developed to calculate monthly average daily global solar radiation in Batman.